A variety of electronic devices such as cell phones, laptop computers, and personal digital assistants to name only a few, may be powered by one or more variable output DC power sources. A variable output DC power source may accept an unregulated input voltage and provide a variable output DC voltage and output current to a load. The unregulated input voltage may be an alternating current (AC) or DC input voltage.
There are many different classes of variable output DC power sources that may be defined by parameters including, but not limited to, input voltage range, maximum output voltage, and maximum output current. Within each class, there may be differing types of variable output DC power sources. Each type may be defined by additional parameters including, but not limited to, maximum output power rating, load regulation, line regulation, and over voltage/current protection features. In a conventional arrangement, each type of variable output DC power source may be designed to couple to particular power control circuitry to control operations thereof. This conventional arrangement decreases design flexibility and increases costs as each variable output DC power source requires particular power control circuitry.
Accordingly, there is a need in the art for power control circuitry that can be utilized with differing types of variable output DC power sources by detecting the type of variable output DC source coupled to it.